Live gasifier burn

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Nofossil

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I made some changes to my graph software. Click on this link for a live graph of the last 120 minutes. Works any time, always gives you the last two hours up to the moment of your click (I hope).

In the graphs, the digital I/O is shown as a broken line - visible when on, gap when off. 'Demand' means that at least one heating zone is calling for heat. Flue and secondary combustion temps are divided by 10 to fit on the same scale, so 90 actually equals 900.

I just started a fire at about 5:15. I'm documenting everything on this burn. For instance, my initial load was 48 pounds. I have pictures I'll post as well, showing the thermocouples and my fire building technique.

I'll update this post with pictures, but for now you graph addicts can watch the burn as it progresses through the link above.

These show the location of the two thermocouples, as well as the amount of creosote in my primary chamber and the lack of creosote elsewhere. Is this pretty much what everyone has with these boilers?
 

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More documentation;

The fire was ignited at 5:17. The lower door and bypass damper were closed six minutes later at 5:23, and the controller was turned on. Gasification kicjked off within 15 seconds.

These photos show the fire construction. Bottom layer is read cedar and white pine. Balance is buckthorn, apple, and locust.
 

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Eager to see the full burn. Thanks Man


Will the sequel be called


"Another 48 pounds"
 
My firebox looks just like yours, nofossil. Your ash is a little finer than mine. (Not that there's anything wrong with that). Somehow you're managing to get a bit cleaner burn than me, which probably has something to do with our respective amounts of idle.

Is that the compromised labyrinth, or did you rebuild it? 'Cause it looks OK to me.
 
At 7:45 (after dinner) I added another 43 lbs of wood - hickory, locust, and buckthorn. The hickory and locust is still pretty green, both around 32-34% moisture. The buckthorn is around 19%. Can't wait until I'm 2 full years ahead.

By the time dinner was done, it had died down to coals that worked out to about a 3" layer when stirred around.

Last week, I rebuilt the labyrinth with 3000 degree high density bricks. All of the 2300 degree lightweight alumina is now gravel.
 

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Summary:

By 6:50, the house is up to temp, the hot water tank is at 160, and the hot tub is up to temp. The storage tank is the only remaining heat load.

The initial load dies down until the boiler is refilled (about 2/3 full: 43 pounds of mostly too-green wood) at about 7:45.

At about 8:30, the outlet temperature got high enough so that the EKO controller starts a series of short idle intervals. These continue as the tank heats up, with the tank top reaching 170 by about 10:00.

At 10:04, the coals are stirred and 3 pounds of wood are added to help the remaining larger chunks to burn out cleanly.
 

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What is your recap on these two burns
94 lbs of wood @ 30 avg moisture @ 75 percent effcient?
Are we looking at 400K btu usable?
Your tank gets from 120 to 170 around 365K right?
I know this is crappy rounding/guessing, you better set me straight.
 
ABGWD4U said:
What is your recap on these two burns
94 lbs of wood @ 30 avg moisture @ 75 percent effcient?
Are we looking at 400K btu usable?
Your tank gets from 120 to 170 around 365K right?
I know this is crappy rounding/guessing, you better set me straight.

I'll do a detailed analysis when I get a few minutes. In addition to the storage tank, the boiler heated a 40 gallon hot water tank from 148 to 160, and heated a 550 gallon hot tub from 96 to 100.

The top of the storage went from about 132 to 177, while the middle only went to 160.
 
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